Portable lamp



FIG.

'0b INVENTOR. RUDOLPH 'PoPP ATTORNEY Patented Dec. 31, 1946 PORTABLE LAMP Rudolf Popp, Valparaiso, Ind., assignor to McGill Manufacturing Company, Inc., Valparaiso, Ind.,

a corporation of Indiana Application October 30, 1943, Serial No. 508,273

(Cl. 24U-54) 3 Claims.

The present invention relates to portable lamps and more particularly to improvements in portable lamps of the so-called vapor sealed type. This application is a continuation in part of copending application Serial No. 503,595, filed September 24, 1943.

Portable lamps of the so-called vapor sealed type employing parts formed of insulating material have long been manufactured for use in areas where static discharges or arcs are to be avoided, due to the presence of inflammable or explosive gases. In a portable lamp of this character, it is particularly important to insulate the lamp bulb against mechanical shock and vibration, not only for the purpose of minimizing filament breakage, but also to minimize the likelihood cf envelope breakage, and, hence, the possibility of gas or vapor ignition. From the standpoint of manufacturing cost, it is also desirable not to employ complicated sealing and shock insulating facilities in the construction of a portable lamp of this type.

It is an object of the present invention, therefore, to provide an improved and simple structure for housing the bulb of a portable lamp within a sealed transparent enclosure.

It is another object of the invention to provide an improved and simple arrangement for minimizing the transmission oi mechanical shock and vibration to the bulb receiving socket through the handle of the device.

According to another object of the invention, at least one of the parts of the sealing structure is also utilized to insulate the lamp receiving socket against shock and vibration occasioned by contact of the portable lamp handle with other objects.

The invention, both as to its organization and method of operation, together with further objects and advantages thereof, will best be understood by reference to the following specification taken in connection with the accompanying drawing, in which:

Fig. l is a side view, partially in section, illustrating a, portablelamp holder provided with improved sealing and shock insulating facilities characterized by the features of the present invention;

Fig. 2 is a top sectional View of the device shown in Fig. 1; and

Fig. 3 is a fragmentary sectional view of a modified sealing and shock insulating structure also characterized lby the features of the present invention.

Referring now to the drawing and more particul`ar1y to Figs. 1 and 2 thereof, the portable lamp there illustrated comprises a handle IQ which is formed of hard insulating material, such as molded Bakelite or the like, capable of transmitting mechanical shock and vibration. At.its upper end, the handle I Il is provided with a flared or enlarged portion Illa having an opening ID'b extending longitudinally thereof for receiving an incandescent lampsocket 35. Integrally formed, radially extending ribs I3 are provided around the circumferential surface of the handle portion IIla, which have countersunk openings Ida therethrough for receiving assembly screws i4 in a manner such that the heads of the screws are not exposed. These screws may be utilized rigidly to support the base I5 of a lamp guard I6 upon the upper platform-like surface of the handle Ill in the manner illustrated. For the purpose of preventing the screws I4 from becoming disassembled from the handle I0 during disassembly of the handle and guard, each opening Ida is counterbored from the top, as indicated at Ilb, to receive a fibre washer I4c which is threaded onto the `associated screw I4. More specifically, each washer I4c is threaded onto the associated screw I4 to a point where it will be disposed only slightly below the undersurface of the guard base I5 when the guard is supported upon the upper surface of the handle. A tight thread fit is utilized in each screw and washer assembly in order to insure rotation of the two parts as a unit and thus prevent the Washer from working loose from the screw. With this arrangement, the screws Ill are loosely locked to the handle when the guard is disassembled therefrom, thereby to prevent the screws from becoming 10st and to facilitate assembly of the guard upon the handle.

The opening I0b through the handle I0 is also utilized to receive the conductors of a cord II, these conductors being connected in the customary manner to the terminals of the lamp socket 35. At its lower end, the handle I0 is provided with a tapped longitudinally extending opening for receiving the external threads of an anchor cap I2, which is also formed of insulating material. This cap is drilled to provide an opening Iza, oi slightly greater diameter than the cord I l and is then counterbored through the threaded end portion thereof to provide an annular space Ib surrounding a section of the cord. Adjacent the upper end of the cap, the handle lil is provided with a transversely extending portion Ic having an opening Id therethrough which is of the same diameter as the opening I2a. A soft rubber sleeve 8 is disposed within the annular space I2b and is of greater length than this space, so that as the cap I2 is threaded into the tapped end of the handle IIJ, the end portions of the sleeve are eX- truded within the spaces between the cord I I and the walls of the two openings Ild and |2a, and the intermediate portions of the sleeve are swelled against the cord and the sides of the bore |2b. Thus the-cord is fiXedly anchored withinthe cap I2 and a hermetic seal is provided for preventing gases or liquids from entering the hollow portion Illb of the handle through the cord open- 1ng.

For the purpose of enclosing a bulb 3i, with which the device is fitted, within asealed gas-tight chamber, a bulb enclosing globe is provided. This globe is in the form of an inverted cup,

is constructed of shatter-proof glass having heavyl wall thickness, and half of the area thereof is enameled or otherwise coated as indicated at 30a to provide a light reflecting surface. At the outer side of the rim portion thereof, the globe 30 is provided with threads 30D which are adapted for engagement with internal threads ille formed in the inner peripheral surface of the recessed end portion of the handle IU. More specifically, the enlarged upper portion Illa of the handle IB is provided with an enlarged cup-shaped opening at which the socket receiving opening Ib terminates. Around the mouth of the socket receiving opening Ib, an annular recess 3l is formed to receive a flexible washer 38 made of soft rubber or the like, in the manner more fully explained below. A fiat platform-like surface lf extending transversely of the handle I is thus provided between the walls of the enlarged cup-shaped opening and the edge of the recess 31. For the purpose of providing a sealed connection between the globe 3D and the handle I0, a soft rubber washer 32 is laid within the cup-shaped recess flat against the surface Illf. This washer is of such dimensions that the outer edge surface thereof is disposed between the edge of the globe 30 and the surface IIJf to be clamped therebetween when the globe 33 is threaded into the threaded portion of the handle I0. Thus, a hermetic seal is formed between the lip of the globe 30 and the handle I0. This seal, in cooperation with the seal provided by the soft rubber sleeve 8, functions to prevent inflammable gases or vapors from entering the chamber within which the bulb 3| is disposed.

As indicated above, the soft rubber washer 33 is utilized resiliently to support the bulb receiving socket 35 within the apertured portion l'b of the handle ID. 'More-specically, the washer 38 entirely fills the annular recess 31 and is partially covered by the inner edge portion of the washer 32. At the upper inner edge thereof, it seats the annular rim or flange portion '35a of the lamp socket 35 in a manner such that the side walls of the socket are displaced Ifrom and out of contact with the surface of the opening Iiib within the handle Ii). The outer periphery of the socket ange is `snugly embraced within the inner periphery of the washer 32, whereby this washer assists in maintaining the'socket 35 located ina position centrally of the opening I-Elb and out of contact with the handle Ill. The flange portion ci the socket 35 is clamped to the handle l' 0 through the flexible washer 38 by means of assembly ele-' ments 34 which bear againstthe upper surface of the socket flange 35a, overlie the rubber washer 32, and are held in clamping engagement with the upper edge of the socket vby `clamping screws 33 which are threaded into the flaredfportion I 4 of the handle I0. Thus, a simple arrangement is provided for sealing the bulb 3| within the globe 30 and for minimizing the transmission of mechanical shock or vibration to the bulb through the socket 35 when the device is dropped or is brought into contact with a vibrating object.

The modified structure shown in Fig. 3 of the drawing is substantially 4similar tothat just described, the principal difference being that in the Fig. 3 arrangement the soft rubber washer 32 lserves the two functions of providing a hermetic seal between the handle II) and the globe 30, and

washer, .32 in` 'performing the last-mentioned function, this washer is provided with an upstanding annular portion 32a of greater longitudinal thickness than the remaining portions of the washer. At the upper edge thereof, the washer portion 32a supports vthe annular rim of the lamp socket 35 in a manner such that 'the' side walls ofthe socket aredisplaced from the inner surface of the opening I'Db within the handle I8. Assembly screws 33 and clamping elements 34, in combination withspacing columns 36, lare utilized to clamp the socket rim '35a to the platform surface Illf of the handle Ill through the thickness of the annular washer portion` 32a. More specifically, each spacer column 36 is inthe form of a sleeve telescoped over one of the assembly screws 33 and is provided with a tapering upper surface, such that a knife edge support is provided for 'the associated clamping element 34 at the end thereof farthest removed from the peripheral edge of the socket flange 35a. Thus, a simple arrangement is provided by which the lamp socket 35 is resilientlysupported upon the handle fill to prevent mechanical shocks from being transmitted to a bulb or lamp supported therein.

While different embodiments of the invention have been disclosed, it will be understood that various modifications may be made therein, which are within the true spirit and scope of the invention.

I claim:

1. In a portable lamp, a handle formed of hard insulating material which is capable of transmitting mechanical shock and vibration, said handle having a socket receiving opening extending longitudinally thereof and an annular recess around the mouth of said opening, a flexible washer filling said recess, a Vlamp socket provided with a flange portion seated upon said washer and supported within ysaid opening solely by said washer, whereby the transmission of mechanical shock and vibration through said handle to said socket -is minimized, a second flexible washer partially overlying said first-named washer and snugly embracing the periphery of said socket flange, and means including said second washer for clamping said socket to saidv handle through said rst-named washer.

2. In a portable lamp which includes a handle provided with an enlarged portion formed of a hard material capable of transmitting mechanical shock and vibration; the combination which includes means formed integral with the enlarged portion of said handle for defining a cupshaped recess whichis concentrically arranged relative to said handle, said handle also havinga socket receiving opening extending longitudinally thereof "and fan' annular recess at the mouthof said opening, a exible washer filling said lastnamed recess, a lamp socket provided with a flange portion seated upon said washer and supported within said opening solely by said Washer, whereby the transmission of mechanical shock and vibration through said handle to said socket is minimized, a second flexible washer partially overlying said rst-named washer and snugly embracing the periphery of said socket flange, means including said second Washer for clamping said socket to said handle through said rstnamed washer, a bulb enclosing globe including a rim portion extending within said cup-shaped recess so that the edge thereof bears against said Second Washer, and means for producing pressure engagement of the edge of said globe with said washer.

3. In a portable lamp which includes a handle provided with an enlarged portion formed of a hard material capable of transmitting mechanical shock and vibration; the combination which includes means formed integral with the enlarged portion of said handle for defining a cup-shaped recess which is concentrically arranged relative to said handle, said handle also having a socket receiving opening extending longitudinally thereof and an annular recess at the mouth of said opening, a flexible washer lling said lastnamed recess, a lamp socket provided with a flange portion seated upon said'washer and supported within said opening solely by said Washer, whereby the transmission of mechanical shock and vibration through said handle to said socket is minimized, a second flexible Washer partially overlying said first-named Washer and snugly embracing the periphery of said socket ange, clamping pieces extending radially across the upper surfaces of said second Washer and socket flange at points around the circumference of said socket flange, clamping screws extending through said second washer and said clamping pieces and threaded into said handle t0 clamp said socket to said handle throughy said first- 'named washer, a bulb enclosing globe including a rim portion extending Within said cup-shaped 

